1. Field of the Invention
The present invention relates to a program product for data communication, a computer-readable recording medium in which a data communication program is recorded, a data communication apparatus, and a data communication method. More particularly, the present invention relates to a data communication program product that can alleviate communication traffic even in the case where the firmware of a plurality of devices connected to, for example, a LAN (Local Area Network), is to be rewritten at the same time, a computer-readable recording medium in which a data communication program is recorded, a data communication apparatus and a data communication method
2. Description of the Related Art
The firmware controlling the operation of, for example, an image formation apparatus is conventionally written into a mask ROM (Read Only Memory). When the firmware has to be exchanged, the method is taken of replacing the mask ROM on the control board in the image formation apparatus with a mask ROM written with new firmware.
The exchange of a mask ROM is time-consuming and complicated. Therefore, a rewritable flash ROM is used instead of a mask ROM to improve the workability.
Methods set forth below have been taken to exchange the firmware written in a flash ROM.
As the first method, the method of using an external storage device such as a memory card is known. An I/F (interface) with an external storage device such as a memory card is provided in the image formation apparatus. A memory card with the new firmware is connected to that I/F. Then, the new firmware is written from the memory card to the flash ROM. In rewriting the firmware, remote operation is not possible. The operation must be carried out actually at the site where the image formation apparatus is installed.
A method of utilizing a public switched network is known as the second method. This method is adapted to practical usage mainly in the field of facsimile apparatuses. Specifically, firmware is transmitted to an image formation apparatus from a remote apparatus connected to the public switched network. By downloading the transmission, the firmware is rewritten. Although there is no need to be actually present at the site as in the first method, the communication cost is high. Also, downloading the firmware is relatively time-consuming.
Reflecting the spread of the Internet, downloading the firmware through the Internet instead of through the public switched network is taken as the third method. The usage of the Internet allows reduction in the cost of transmission and the time required to download the firmware.
There are various protocols for communication through the Internet such as an HTTP (Hyper Text Transfer Protocol) to view a home page, an FTP (File Transfer Protocol) to transfer a file, an SMTP (Simple Mail Transfer Protocol) used in the communication of electronic mail, and the like. However, the protocol to download the firmware from a remote station to an image formation apparatus through the Internet is limited from the standpoint of security on the communication through the Internet.
Specifically, a firewall generally functioning as a “barrier” is provided at the connection of the Internet and each user to cope with illegal access and the like from the Internet to the user's internal system. The firewall has the capability to control the communication protocol that can be passed between the Internet and the internal system of the user. Accordingly, the passable protocol is limited. The protocol of electronic mail is generally set as passable. Therefore, the conventional electronic mail system is employed in transmitting firmware via the Internet.
The above third method, i.e., the method of transmitting firmware utilizing an electronic mail system has the possibility of increasing the communication traffic of the Internet and the LAN as well as the load on the mail server. No measures have been taken to cope with these issues.
For example, consider the case where one user possessing a plurality of image formation apparatuses of the same type is to alter the firmware in these image formation apparatuses simultaneously. In the conventional firmware transmission method, the same firmware must be transmitted individually to each image formation apparatus.
The size of the firmware in an image formation apparatus has now become as big as approximately 10 Mbytes in accordance with the high function and multi-feature thereof. It is expected that the size of the firmware will further increase in the future.
This means that multiple transmission of firmware of such large size will significantly increase the communication traffic of the Internet as well as the LAN on both the transmission and receiver sides. Also, the load on the mail server for both the transmission and receiver sides is great.